Basic oxygen furnace bottom Rising causes
stagnant zone existence
Basic oxygen furnace: Reasonable Oxygen lance design requirement oxygen fluid jet Firstly meet smelting supplying oxygen intensity、molten iron、scrap、slag materials etc chemical reaction uniform. Meanwhile requires jet impact depth, not jet furnace bottom. A stagnant zone can shrink to the minimum rang. After that Make in the molten bath liquid metal as far as possible participate circulating flow.
- When The jet impact not able basic oxygen furnace blowing, Oxygen jet enters the liquid metal, Formation to a pit. Its central part achieves the biggest depth. Call it jet impact depth. It to molten bath mixing、steel making Chemical reaction and furnace bottom corrosion or rising has close influence. For example, The Jet impact depth big, The Stagnant zone reduces or disappears. Furnace bottom corrosion serious, not easy Rising. And contrary, easy rising.
- When used multi-hole oxygen lance, The Nozzle head included angle not reasonable. On the nozzle head, Hole and hole included angle or interval distance, For fluid jet has a severe impact. The included angle reduce, Can Cause to fluid jet stream among, The traction increase. As a result, fluid jet stream draws close trend more obvious, The stagnant zone reduces, And The furnace bottom Rising slow. And contrary, easy rising.
Furnace chamber internal structure not reasonable
Before the basic oxygen furnace campaign, The furnace lining internal structure reasonable. In the molten bath liquid metal good circulation, In the steelmaking Chemical reaction go on well. Not usually appear furnace bottom Rising phenomenon. When The basic oxygen furnace campaign enters Metaphase\anaphase\ furnace lining corrosion serious. To prevent appear basic oxygen furnace leak. Adopt to slag splashing and repair furnace methods to solve. Cause to molten bath liquid metal began to rise. Oxygen lance nozzle head and furnace bottom distance change to larger. The original operation mode has already can not drive the molten bath bottom liquid metal to participate to cycle. Influence furnace bottom.
1. The Slag splashing protect the furnace influence
The Slag splashing protects the furnace. Mainly using high-pressure resistance N2. Through Oxygen lance fluid jet to residual to furnace slag after output Steel. In addition, Through airflow powerful force, Make furnace slag splashing to the furnace chamber. Formation to tough slag coating. so, Slow down to furnace lining corrosion, To protect furnace lining.
When appearing the slag splashing lance position so high or N2 pressure resistance small or furnace slag physicochemical properties bad or Residual furnace slag small or more amount cases. Lead to the furnace bottom Rising.
2.Repair to the furnace influence
Frequent using paste brick or furnace burden, Maintenance furnace lining/basic oxygen furnace chamber internal structure, Happen Irregular variation. In addition, Due to the furnace burden conglutinating repair, Take up furnace chamber volume. So, Make molten bath liquid metal rising, The Oxygen lance nozzle head and furnace bottom distance change to larger. The oxygen fluid jet can not drive molten bath bottom liquid metal to participate in circulation. Corrosion can not to the furnace bottom.
Furnace slag nature unreasonable
basic oxygen furnace blowing metaphase/anaphase, Due to various reasons, Cause slag melting bad or furnace slag sticky. After out steel, Directly slag splashing. Cause furnace slag can not splash to the furnace wall. After slag splashing, furnace bottom can not pour out residua. The next furnace, After loading molten iron and scrap, It temperature drop. When the blowing, In the stagnant zone liquid metal can not drive to residua rising. So, Residua and liquid metal at the same time viscosity to the furnace bottom. Similarly, Many aspects of factors lead to the steel-slag stagnate the furnace bottom.
Lead to the furnace bottom rising. The liquid metal can not participate in circulation.